The Throw-In (Suteishi) in Go: Sacrifice a Stone to Capture

⏱ Read ~5 min · Updated July 2026 · Part of: Learn Go

A throw-in (sacrifice stone, Japanese: suteishi, 扑) is a clever tesuji: you deliberately play a stone where it will be captured — and that sacrifice wrecks the opponent's eye shape or steals their liberties, winning you the fight.

1. Why sacrifice a stone?

Giving away a stone sounds counterintuitive. But a throw-in does two things:

• Destroys eye shape — play on the vital point where the opponent wants to make an eye, preventing two eyes and killing the group.
• Reduces liberties — in a capturing race, the sacrificed stone steals a liberty from the opponent's group (it gets captured, but the capture process costs the opponent a liberty).

🎁 Analogy: a throw-in is like giving the opponent a gift that forces them to spend a move unwrapping it — and while they're unwrapping, you take the real prize (eye shape / liberties / sente).

2. What a throw-in looks like (board illustration)

White wants to make eyes and live; Black deliberately throws a stone deep into White's shape:

Black (1,1) plays inside the white group — it will be captured. But once White captures it, White's eye shape is destroyed (that point was potentially an eye). Black sacrifices one stone to make White unable to make two eyes = White dies.

3. The throwing-in capture — the most satisfying version

You throw in a stone, the opponent captures it… but the capture puts their own stones in atari, so you recapture — bigger. The sacrifice reversed the fight.

😱 Beginners never see it coming. They happily capture the "free" stone, then lose three. The throwing-in capture is the classic "small sacrifice, big return" — give up one stone, capture a group.

4. When to use a throw-in

• The opponent wants to make two eyes → throw in on the point that splits their eye space (destroy the eye).
• A capturing race is close → throw in to steal a liberty (reduce their count).
• You can set up a recapture (throwing-in capture) → sacrifice, lure the capture, then recapture bigger.
• To create a ko → throw-ins are a common way to create ko shapes (the opponent captures your throw-in stone → ko forms).

5. The 4 most common throw-in mistakes for beginners

1. Not thinking "sacrifice" is the answer. Throw-ins are deeply counterintuitive — "play where I'll be captured" violates beginner instinct. But many puzzle solutions are throw-ins (eye destruction / liberty reduction / recapture). When reading, ask yourself "is there a throw-in?"
2. Throwing in at the wrong point. A throw-in must be on a vital point (eye space / key point). Throwing in at an irrelevant point = pure donation. Find the right point.
3. Not reading the recapture. After the opponent captures your throw-in, is your recapture actually possible? Read it through — if capturing doesn't put them in atari, your throw-in was a wasted stone.
4. Not throwing in when you should (missing eye destruction). The opponent is about to make two eyes, you don't throw in to destroy, and they live. When you see eye shape forming, throw in first to break it.

6. Throw-ins on the 4×4 board

The small board makes throw-ins easy to verify: you can read the sacrifice and recapture completely. Many 4×4 capture puzzles hinge on a throw-in that destroys the only possible eye — the "correct answer" is the sacrifice, not a capture. The brainGO engine can verify these throw-in puzzles (type=throw-in).

How to train it

Train with puzzles where "the answer is a sacrifice" — feel the reversal.

👉 Play brainGO — the throw-in tesuji

FAQ

What is a throw-in and why sacrifice a stone?

A throw-in plays a stone where it will be captured, to destroy the opponent's eye shape or reduce their liberties. You give up one stone to gain something bigger (they can't make eyes / fewer liberties / you recapture). Counterintuitive but powerful tesuji.

What is a throwing-in capture?

You throw in a stone, the opponent captures it, but capturing puts their own stones in atari — you recapture bigger. Sacrifice one stone, capture a group. The most satisfying throw-in version.

How does a throw-in differ from a ladder or net?

Ladders and nets are "chase or surround to capture the opponent." A throw-in is "give the opponent a stone to capture, to destroy their shape." Ladders/nets capture directly; throw-ins work indirectly (sacrifice for gain).

When should I throw in?

① The opponent wants to make two eyes (throw in to destroy the eye); ② a capturing race is tight (throw in to steal a liberty); ③ you can recapture (throw in → recapture bigger); ④ you want to create a ko. When you see these situations, ask "is there a throw-in?"

How do I find the "vital point" for a throw-in?

The vital point is usually the intersection where the opponent wants to make an eye — the point where, if they play there, they get two eyes and live. The test: look at their shape and find the single point where "if they play, they live; if you play, they can't make two eyes." Throwing in at an irrelevant point is a pure donation; throwing in at the eye vital point means one sacrificed stone decides life and death. On the 4×4 board the small space often makes this point obvious at a glance.

What if the opponent captures my throw-in but isn't in atari?

Then you misread — this throw-in was a free donation. A throw-in only works if "after they capture, either their eye shape is wrecked, or their own stones are in atari (throwing-in capture)." If neither happens after the capture, the point was never vital to begin with, or they had another connection. When reading, push "they capture → and then what?" all the way to the end, confirm the sacrifice actually buys something, then play it.

Related guides

• Learn Go: the visual beginner's guide — the beginner hub (this article's home)
• The eye — what a throw-in destroys
• Basic life-and-death shapes — vital points for throw-ins
• Capturing race (semeai) — throw-ins steal liberties here
• Ko — throw-ins create ko shapes
• Capture — the recapture after a throw-in
• Glossary — various local tesuji